Prefabricated corner for dry wall and plaster construction

ABSTRACT

A prefabricatd three-sided corner for dry wall and plaster construction possesses the shape of the interior of a trigonal pyramid with orthogonal sides from which triangular shaped panels are missing. The prefabricated corner preferably is made of high impact polystyrene with a semi-smooth surface, and has a thickness of 0.025 inches.

DESCRIPTION OF THE INVENTION

[0001] This invention fits into the category of being an article of manufacture for the building construction industry. More specifically, it is an article of manufacture for dry wall and plaster construction. Finally, this invention is a prefabricated three-sided corner for dry wall and plaster construction.

[0002] In building construction, an three-sided corner is formed wherever two walls and a ceiling meet. Usually, the two walls and the ceiling are mutually perpendicular to each other so that there is a 90° angle between the two walls and 90° angles between each wall and the ceiling.

[0003] In the case of dry wall, the three-sided corner will be located at the junction of three sheets of dry wall which have been nailed onto wall studs. There will be cracks or spaces in the seams between the three dry wall sheets forming the three-sided corner. Dry wall compound is used along with dry wall tape to cover up these spaces or joints between dry wall sheets. In the case of plaster construction, the three-sided corner will be located at the junction of three sheets of wooden slats which have been nailed onto wall studs. The sheets of wooden slats will be covered over with plaster and the plaster will be applied so as to leave no gaps between the junctions of walls and ceiling.

[0004] The usual manner of finishing a three-sided corner in dry wall construction is as follows: The dry wall sheets forming the three-sided corner are nailed to wall studs. Dry wall tape is applied by machine (Banjo or Bazooka) or manually along each of the three two sided corners with dry wall tape overlapping ½ over the vertex of the three sided corner. Dry wall compound is applied to cover the edges of the dry wall tape and a three-sided finished corner is shaped by skillful perpendicular swipes of a spatula designed to apply dry wall compound to cover the cracks. When the three-sided corner is dry, it is then painted.

[0005] The usual manner of finishing a three-sided corner in plaster construction is as follows: The sheets of wooden slats forming the three sided corner are nailed onto wall studs. Plaster is applied to the wooden slats to make planar wall and ceiling surfaces. The spatula used to apply plaster is used to make the three-sided corner by perpendicular swipes of the spatual blade. When the three-sided corner is dry, it is then painted.

[0006] The problem with making three-sided corners in dry wall or plaster construction is that it requires considerable skill and it also is time consuming. The trick is to get all the angles to be exactly 90° all along the two-sided corners right up to the vertex of the three-sided corner.

[0007] It is an object of the present invention to solve this problem of making perfect three-sided corners in dry wall and plaster construction by providing prefabricatd three-sided corners which possess perfect 90° angles between the three planes of the corner.

[0008] The present invention is shown in the accompanying drawings.

[0009]FIG. 1 shows a perspective view of the invention looking up into the interior of the prefabricated three-sided corner.

[0010]FIG. 2 shows a side view of the invention when the invention as shown in FIG. 1 is rotated 135° to the right and tilted slightly downward.

[0011]FIG. 3 shows a side view of the invention when the invention as shown in FIG. 1 is rotated 135° to the left and tilted slightly downward.

[0012] Referring to FIGS. 1, 2, and 3 simultaneously, it is seen that this prefabricated three-sided corner possesses three planar sides 14, 20, and 34 which are orthogonal to each other. Thus There is a 90° angle between side 14 and 20 and between 14 and 34 and between 20 and 34. The three sides just mentioned form a vertex 23 from which radiate the junctions 19, 27, and 36 of the planar sides of the invention.

[0013] In a sense, the three-sided corner possesses three arms 16, 30, and 41 that are mutually perpendicular to each other. Arm 16 is defined by the vertex 11, the edge 12, the vertex 13, edge 15, vertx 17, edge 18, vertex 21, edge 22, and vertex 24. Arm 30 is defined by vertex 24, edge 25, vertex 26, edge 28, vertex 29, edge 31, vertex 32, edge 33, and vertex 35. Arm 41 is defined by vertex 35, edge 36, vertex 38, edge 39, vertex 40, edge 42, vertex 43, edge 44, and vertex 11.

[0014] Another way of characterizing this invention is to say that this invention is a preformed three-sided corner in the shape of the interior of a trigonal, or three-sided, pyramid, in which the sides of the pyramid are orthogonal, and in which a triangle-shaped panel has been removed from each side of the orthogonal trigonal pyramid. Thus, the base of the pyramid shown in FIGS. 1, 2, and 3 is defined by the edges 42 and 15, edges 18 and 28, and edges 31 and 39. The absent triangular panels are defined by the edges 44, 12, and a line connecting vertices 43 and 23; the edges 22, 25, and a line connecting vertices 21 and 26; and the edges 34, 36, and a line connecting vertices 32 and 38.

[0015] All angles of the preferred embodiment of the invention will now be given: As previously mentioned, sides 14, 20, and 34 are each at 90° angles with respect to the other such sides. In addition, edges 44 and 13 form a 90° angle at vertex 11, edges 22 and 25 form a 90° angle at vertex 24, and edges 33 and 36 form a 90° angle at vertex 35. Edges 12 and 15 form a 135° angle at vertex 13, edges 18 and 22 form a 135° angle at vertex 21, edges 25 and 28 form a 135° angle at vertex 26, edges 31 and 33 form a 135° angle at vertex 32, edges 36 and 39 form a 135° angle at vertx 38, and edges 42 and 44 form a 135° angle at vertex 43.

[0016] The thickness of the preferred embodiment of the invention is 0.025″.

[0017] Length measurements of the preferred embodiment of the invention are as follows: The two-sided corners 19, 27, and 37 are each 4″ long. The edges 12, 22, 25, 33, 36, and 44 are each 2″ long. Finally, the edges 15, 18, 28, 31, 39, and 42 are each 1½″ long.

[0018] The preferred embodiment of the invention is made by injection mold to form a rigid plastic material such as high impact polystyrene with a semi-smooth surface.

[0019] The present invention is used in the following manner: In the case of dry wall construction, a crude three-sided corner is formed by sheets of dry wall meeting at right angles to form a crude vertex. Next, the prefabricated corner as shown in the Figures is attached to the crude dry wall corner by spraying the crude dry wall corner with a spray glue and immediately pressing the prefabricated three-sided corner into the crude dry wall corner. The preferred spray glue contains n-hexane dimethyl ether and acetone. The glue dries quickly and the prefabricated corner remains stuck to the crude dry wall corner. At this point as shown in FIG. 1, side 14 of the prefabricated corner will be flat against the ceiling of the room undere construction, side 20 will be flat against the right wall of the room, and side 34 will be flat against the left wall of the room.

[0020] Next, dry wall tape is applied to the length of the two sided corners formed by the junctions of the ceiling and two walls of the room. Whereas before, without the use of this invention, the dry wall tape would have been run right up to the very vertex of the crude dry wall three-sided corner, with the use of this invention, the dry wall tape is stopped 2½″ from the vertex of the room's three-sided corner. After the dry wall tape has been applied to the dry wall sheeting and been given time to dry, the putty-like, white dry wall compound is smeared with a spatula over all exposed edges of the construction to give a flat unblemished finish. It is only necessary to apply the dry wall compound to within ½″ of the border of the prefabricated three-sided corner because the white semi-smooth surfce of the prefabricated corner is actually already in a finished state. After the dry wall compound has had a chance to dry, the room and its three-sided corner is ready to be painted.

[0021] In the case of plaster construction, a crude three-sided corner is formed by sheets of wooden slats meeting at right angles to form a crude vertex. Next, the plaster is applied to the wooden slats and made to have a smooth surface with a spatula, resulting in a crude plaster three-sided corner. The prefabricated corner shown in the Figures is attached to the crude plaster corner by either placing the prefabricated corner inot the crude plaster corner when the plaster is still wet, or by waiting for the crude plaster corner to dry first, and then applying the prefabricated corner to the dry crude plaster corner with the spray glue mentioned previously. Additional plaster is used to cover over the edges of the prefabricated corner and smoothed to a uniformly flat surface. The room corner is then ready for painting.

[0022] Shown in the Figures accompanying this disclosure is only the preferred embodiment of the present invention of a prefabricated three-sided corner for dry wall and plaster construction. Another variant of the invention is a prefabricated corner in the shape of the complete shell of a trigonal pyramid with orthogonal sides. In this case, there are no missing triiangular shaped panels in the sides of the pyramid. In this case, there is a solid edge running from point 43 to 13, from point 21 to 26, and from point 32 to 38 in the accompanying Figures. The embodiment actually shown in the Figures is preferred because, the embodiment with the missing triangular panels requires less high impact polystyrene to make each prefabricated corner, thus making it more economical.

[0023] Another embodiment of the invention differes from the embodiment shown in that the ends of the three orthogonal arms 16, 30, and 41, of the corner are flat ends instead of the pointed ends 17, 29, and 40 that are shown in the Figures. In this case, the prefabricated corner would still be essentially in the shape of the shell of a trigonal orthogonal pyramid, but the pyramid would not have a planar base. The pointed ends 17, 29, and 40 of the arms 16, 30, and 41 are preferred over flat ends because the pointed ends allow more uniform drying of the plastic in the injection mold that is making the prefabricated corner.

[0024] It will thus be apparent that a number of modifications such as changes in size, angles, and material substance used can be made in the practice of this invention without departing from from the scope of the invention. 

What is claimed is:
 1. A prefabricated three-sided corner for dry wall and plaster construction in the shape of the interior of a trigonal pyramid with orthogonal sides.
 2. A prefabricated three-sided corner for dry wall and plaster construction in the shape of the interior of a trigonal pyramid with orthogonal sides from which triangular panels are missing.
 3. A prefabricated three-sided corner for dry wall and plaster construction essentially in the shape of the interior of a trigonal pyramid with orthogonal sides from which triangular panels are missing, but where the three resulting orthogonal arms of the resulting corner are squared off instead of pointed.
 4. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 1 wherein the prefabricated corner is made of a rigid plastic material with a semi-smooth surface.
 5. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 2 wherein the prefabricated corner is made of a rigid plastic material with a semi-smooth surface.
 6. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 3 wherein the prefabricated corner is made of a rigid plastic material with a semi-smooth surface.
 7. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 4 wherein the rigid plastic material is high impact polystyrene.
 8. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 5 wherein the rigid plastic material is high impact polystyrene.
 9. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 6 wherein the rigid plastic material is high impact polystyrene.
 10. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 1 wherein the thickness of the prefabricated corner is 0.025 inches.
 11. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 2 wherein the thickness of the prefabricated corner is 0.025 inches.
 12. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 3 wherein the thickness of the prefabricated corner is 0.025 inches.
 13. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 4 wherein the thickness of the prefabricated corner is 0.025 inches.
 14. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 5 wherein the thickness of the prefabricated corner is 0.025 inches.
 15. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 6 wherein the thickness of the prefabricated corner is 0.025 inches.
 16. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 7 wherein the thickness of the prefabricated corner is 0.025 inches.
 17. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 8 wherein the thickness of the prefabricated corner is 0.025 inches.
 18. A prefabricated three-sided corner for dry wall and plaster construction as described in claim 9 wherein the thickness of the prefabricated corner is 0.025 inches. 